HaMLet is a faithful and complete implementation of the Standard
ML programming language (SML'97). It aims to be

  * an accurate reference implementation of the language specification,
  * a platform for experimentation with the language semantics or
    extensions to it,
  * a useful tool for educational purposes.

The implementation is intended to be as direct a translation of
the language formalisation found in the Definition of Standard ML
as possible, modulo bug fixes. It tries hard to get all details of
the Definition right. The HaMLet source code

  * implements complete Standard ML,
  * closely follows the structure of the Definition, with lots of
    cross references,
  * conforms to the latest version of the Standard ML Basis Library,
    is written entirely in Standard ML, with the ability to bootstrap,
  * may readily be compiled with SML/NJ, MLton, Moscow ML, Poly/ML,
    Alice ML, the ML Kit, or SML#.

Homepage:
https://people.mpi-sws.org/~rossberg/hamlet/
